The present invention relates generally to a collapsible shelter means utilizing a pair of panel supporting collapsible frame means arranged at opposed ends of the shelter. Specifically, the structure of the present invention provides improved and durable collapsible end frames, wherein the frames are easily and readily erected, and while erected, are maintained in stable disposition. Specifically, bracing strut means are provided between alternate outer apices of the lazy-tong structure so as to add rigidity to the structure when erect, and further to facilitate ease of collapsing, whenever desired.
In the past, collapsible shelter means have been proposed and described utilizing pairs of collapsible frame means at the opposed ends thereof. In certain instances, lazy-tong structures have been proposed and utilized for this purpose. Generally speaking, however, the lazy-tong structure, while providing ease of erection, has only been of limited utility. Two major problems have been encountered, the first being that of ease of erection, with each of erection being limited to those collapsible shelters of relatively small size. The other problem deals with lack of stability in the presence of wind loads or other forces. In the presence of unusual external loading, the conventional lazy-tong structures become unstable and sometimes tend to assume anomalous configurations, and furthermore may inadvertently collapse. The structure of the present invention is provided with means to assist erection, and by the same token to resist inadvertent collapse, and furthermore to provide a stable and durable construction when in erect form to resist external loading.
Specifically, the collapsible shelter means of the present invention utilizes improved collapsible frame means disposed at opposed ends thereof, with such opposed frame means being mirror images of each other. In this connection, strut means or bracing means are provided at and between adjacent spaced apart outer apices of the lazy-tong structure, with the strut means thereby providing a means of rendering the overall frame means both rigid and durable. Furthermore, the inner apices are designed so as to permit pairs of mutually adjacent links to be coupled together to form a straight linear angle of substantially 180.degree., thereby further enhancing the rigidity of the overall structure. When erect, therefore, the frame means provides a durable truss arrangement which provides both durability and stability to the overall shelter. With the arrangement of the straight angle for the inner apices, these apices form a pattern which substantially circumscribes a circle, generally a semicircle, of fixed radius. The inner apices are defined as those points at which mutually adjacent links meet and are joined together. As a further feature, means are provided for coupling or linking the bracing strut means together for either simultaneous or serial disengagement of these strut means, thereby facilitating collapse of the structure whenever desired. In certain instances, it is desirable to couple together the disengagement means, thereby permitting a single operator to simultaneously disengage the strut means from both collapsible frame means at the opposed ends of the collapsible structure.
As a feature of facilitating ease of folding of the panels supported by the opposed frames, each of the panels is coupled to the frames at the cross points of the lazy-tong structure, and the inner apices, upon folding, are arranged to provide a taut segment in the folded member. This arrangement facilitates storage without adversely affecting the fabric, and contributes to the compact folding of the overall structure.